src/view/renderer.js
/**
* @license Copyright (c) 2003-2020, CKSource - Frederico Knabben. All rights reserved.
* For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license
*/
/* globals Node */
/**
* @module engine/view/renderer
*/
import ViewText from './text';
import ViewPosition from './position';
import { INLINE_FILLER, INLINE_FILLER_LENGTH, startsWithFiller, isInlineFiller } from './filler';
import mix from '@ckeditor/ckeditor5-utils/src/mix';
import diff from '@ckeditor/ckeditor5-utils/src/diff';
import insertAt from '@ckeditor/ckeditor5-utils/src/dom/insertat';
import remove from '@ckeditor/ckeditor5-utils/src/dom/remove';
import ObservableMixin from '@ckeditor/ckeditor5-utils/src/observablemixin';
import CKEditorError from '@ckeditor/ckeditor5-utils/src/ckeditorerror';
import isText from '@ckeditor/ckeditor5-utils/src/dom/istext';
import isNode from '@ckeditor/ckeditor5-utils/src/dom/isnode';
import fastDiff from '@ckeditor/ckeditor5-utils/src/fastdiff';
import env from '@ckeditor/ckeditor5-utils/src/env';
/**
* Renderer is responsible for updating the DOM structure and the DOM selection based on
* the {@link module:engine/view/renderer~Renderer#markToSync information about updated view nodes}.
* In other words, it renders the view to the DOM.
*
* Its main responsibility is to make only the necessary, minimal changes to the DOM. However, unlike in many
* virtual DOM implementations, the primary reason for doing minimal changes is not the performance but ensuring
* that native editing features such as text composition, autocompletion, spell checking, selection's x-index are
* affected as little as possible.
*
* Renderer uses {@link module:engine/view/domconverter~DomConverter} to transform view nodes and positions
* to and from the DOM.
*/
export default class Renderer {
/**
* Creates a renderer instance.
*
* @param {module:engine/view/domconverter~DomConverter} domConverter Converter instance.
* @param {module:engine/view/documentselection~DocumentSelection} selection View selection.
*/
constructor( domConverter, selection ) {
/**
* Set of DOM Documents instances.
*
* @readonly
* @member {Set.<Document>}
*/
this.domDocuments = new Set();
/**
* Converter instance.
*
* @readonly
* @member {module:engine/view/domconverter~DomConverter}
*/
this.domConverter = domConverter;
/**
* Set of nodes which attributes changed and may need to be rendered.
*
* @readonly
* @member {Set.<module:engine/view/node~Node>}
*/
this.markedAttributes = new Set();
/**
* Set of elements which child lists changed and may need to be rendered.
*
* @readonly
* @member {Set.<module:engine/view/node~Node>}
*/
this.markedChildren = new Set();
/**
* Set of text nodes which text data changed and may need to be rendered.
*
* @readonly
* @member {Set.<module:engine/view/node~Node>}
*/
this.markedTexts = new Set();
/**
* View selection. Renderer updates DOM selection based on the view selection.
*
* @readonly
* @member {module:engine/view/documentselection~DocumentSelection}
*/
this.selection = selection;
/**
* Indicates if the view document is focused and selection can be rendered. Selection will not be rendered if
* this is set to `false`.
*
* @member {Boolean}
*/
this.isFocused = false;
/**
* The text node in which the inline filler was rendered.
*
* @private
* @member {Text}
*/
this._inlineFiller = null;
/**
* DOM element containing fake selection.
*
* @private
* @type {null|HTMLElement}
*/
this._fakeSelectionContainer = null;
}
/**
* Marks a view node to be updated in the DOM by {@link #render `render()`}.
*
* Note that only view nodes whose parents have corresponding DOM elements need to be marked to be synchronized.
*
* @see #markedAttributes
* @see #markedChildren
* @see #markedTexts
*
* @param {module:engine/view/document~ChangeType} type Type of the change.
* @param {module:engine/view/node~Node} node Node to be marked.
*/
markToSync( type, node ) {
if ( type === 'text' ) {
if ( this.domConverter.mapViewToDom( node.parent ) ) {
this.markedTexts.add( node );
}
} else {
// If the node has no DOM element it is not rendered yet,
// its children/attributes do not need to be marked to be sync.
if ( !this.domConverter.mapViewToDom( node ) ) {
return;
}
if ( type === 'attributes' ) {
this.markedAttributes.add( node );
} else if ( type === 'children' ) {
this.markedChildren.add( node );
} else {
/**
* Unknown type passed to Renderer.markToSync.
*
* @error renderer-unknown-type
*/
throw new CKEditorError( 'view-renderer-unknown-type: Unknown type passed to Renderer.markToSync.', this );
}
}
}
/**
* Renders all buffered changes ({@link #markedAttributes}, {@link #markedChildren} and {@link #markedTexts}) and
* the current view selection (if needed) to the DOM by applying a minimal set of changes to it.
*
* Renderer tries not to break the text composition (e.g. IME) and x-index of the selection,
* so it does as little as it is needed to update the DOM.
*
* Renderer also handles {@link module:engine/view/filler fillers}. Especially, it checks if the inline filler is needed
* at the selection position and adds or removes it. To prevent breaking text composition inline filler will not be
* removed as long as the selection is in the text node which needed it at first.
*/
render() {
let inlineFillerPosition;
// Refresh mappings.
for ( const element of this.markedChildren ) {
this._updateChildrenMappings( element );
}
// There was inline filler rendered in the DOM but it's not
// at the selection position any more, so we can remove it
// (cause even if it's needed, it must be placed in another location).
if ( this._inlineFiller && !this._isSelectionInInlineFiller() ) {
this._removeInlineFiller();
}
// If we've got the filler, let's try to guess its position in the view.
if ( this._inlineFiller ) {
inlineFillerPosition = this._getInlineFillerPosition();
}
// Otherwise, if it's needed, create it at the selection position.
else if ( this._needsInlineFillerAtSelection() ) {
inlineFillerPosition = this.selection.getFirstPosition();
// Do not use `markToSync` so it will be added even if the parent is already added.
this.markedChildren.add( inlineFillerPosition.parent );
}
for ( const element of this.markedAttributes ) {
this._updateAttrs( element );
}
for ( const element of this.markedChildren ) {
this._updateChildren( element, { inlineFillerPosition } );
}
for ( const node of this.markedTexts ) {
if ( !this.markedChildren.has( node.parent ) && this.domConverter.mapViewToDom( node.parent ) ) {
this._updateText( node, { inlineFillerPosition } );
}
}
// Check whether the inline filler is required and where it really is in the DOM.
// At this point in most cases it will be in the DOM, but there are exceptions.
// For example, if the inline filler was deep in the created DOM structure, it will not be created.
// Similarly, if it was removed at the beginning of this function and then neither text nor children were updated,
// it will not be present.
// Fix those and similar scenarios.
if ( inlineFillerPosition ) {
const fillerDomPosition = this.domConverter.viewPositionToDom( inlineFillerPosition );
const domDocument = fillerDomPosition.parent.ownerDocument;
if ( !startsWithFiller( fillerDomPosition.parent ) ) {
// Filler has not been created at filler position. Create it now.
this._inlineFiller = addInlineFiller( domDocument, fillerDomPosition.parent, fillerDomPosition.offset );
} else {
// Filler has been found, save it.
this._inlineFiller = fillerDomPosition.parent;
}
} else {
// There is no filler needed.
this._inlineFiller = null;
}
this._updateSelection();
this._updateFocus();
this.markedTexts.clear();
this.markedAttributes.clear();
this.markedChildren.clear();
}
/**
* Updates mappings of view element's children.
*
* Children that were replaced in the view structure by similar elements (same tag name) are treated as 'replaced'.
* This means that their mappings can be updated so the new view elements are mapped to the existing DOM elements.
* Thanks to that these elements do not need to be re-rendered completely.
*
* @private
* @param {module:engine/view/node~Node} viewElement The view element whose children mappings will be updated.
*/
_updateChildrenMappings( viewElement ) {
const domElement = this.domConverter.mapViewToDom( viewElement );
if ( !domElement ) {
// If there is no `domElement` it means that it was already removed from DOM and there is no need to process it.
return;
}
const actualDomChildren = this.domConverter.mapViewToDom( viewElement ).childNodes;
const expectedDomChildren = Array.from(
this.domConverter.viewChildrenToDom( viewElement, domElement.ownerDocument, { withChildren: false } )
);
const diff = this._diffNodeLists( actualDomChildren, expectedDomChildren );
const actions = this._findReplaceActions( diff, actualDomChildren, expectedDomChildren );
if ( actions.indexOf( 'replace' ) !== -1 ) {
const counter = { equal: 0, insert: 0, delete: 0 };
for ( const action of actions ) {
if ( action === 'replace' ) {
const insertIndex = counter.equal + counter.insert;
const deleteIndex = counter.equal + counter.delete;
const viewChild = viewElement.getChild( insertIndex );
// The 'uiElement' is a special one and its children are not stored in a view (#799),
// so we cannot use it with replacing flow (since it uses view children during rendering
// which will always result in rendering empty element).
if ( viewChild && !viewChild.is( 'uiElement' ) ) {
this._updateElementMappings( viewChild, actualDomChildren[ deleteIndex ] );
}
remove( expectedDomChildren[ insertIndex ] );
counter.equal++;
} else {
counter[ action ]++;
}
}
}
}
/**
* Updates mappings of a given view element.
*
* @private
* @param {module:engine/view/node~Node} viewElement The view element whose mappings will be updated.
* @param {Node} domElement The DOM element representing the given view element.
*/
_updateElementMappings( viewElement, domElement ) {
// Remap 'DomConverter' bindings.
this.domConverter.unbindDomElement( domElement );
this.domConverter.bindElements( domElement, viewElement );
// View element may have children which needs to be updated, but are not marked, mark them to update.
this.markedChildren.add( viewElement );
// Because we replace new view element mapping with the existing one, the corresponding DOM element
// will not be rerendered. The new view element may have different attributes than the previous one.
// Since its corresponding DOM element will not be rerendered, new attributes will not be added
// to the DOM, so we need to mark it here to make sure its attributes gets updated. See #1427 for more
// detailed case study.
// Also there are cases where replaced element is removed from the view structure and then has
// its attributes changed or removed. In such cases the element will not be present in `markedAttributes`
// and also may be the same (`element.isSimilar()`) as the reused element not having its attributes updated.
// To prevent such situations we always mark reused element to have its attributes rerenderd (#1560).
this.markedAttributes.add( viewElement );
}
/**
* Gets the position of the inline filler based on the current selection.
* Here, we assume that we know that the filler is needed and
* {@link #_isSelectionInInlineFiller is at the selection position}, and, since it is needed,
* it is somewhere at the selection position.
*
* Note: The filler position cannot be restored based on the filler's DOM text node, because
* when this method is called (before rendering), the bindings will often be broken. View-to-DOM
* bindings are only dependable after rendering.
*
* @private
* @returns {module:engine/view/position~Position}
*/
_getInlineFillerPosition() {
const firstPos = this.selection.getFirstPosition();
if ( firstPos.parent.is( 'text' ) ) {
return ViewPosition._createBefore( this.selection.getFirstPosition().parent );
} else {
return firstPos;
}
}
/**
* Returns `true` if the selection has not left the inline filler's text node.
* If it is `true`, it means that the filler had been added for a reason and the selection did not
* leave the filler's text node. For example, the user can be in the middle of a composition so it should not be touched.
*
* @private
* @returns {Boolean} `true` if the inline filler and selection are in the same place.
*/
_isSelectionInInlineFiller() {
if ( this.selection.rangeCount != 1 || !this.selection.isCollapsed ) {
return false;
}
// Note, we can't check if selection's position equals position of the
// this._inlineFiller node, because of #663. We may not be able to calculate
// the filler's position in the view at this stage.
// Instead, we check it the other way – whether selection is anchored in
// that text node or next to it.
// Possible options are:
// "FILLER{}"
// "FILLERadded-text{}"
const selectionPosition = this.selection.getFirstPosition();
const position = this.domConverter.viewPositionToDom( selectionPosition );
if ( position && isText( position.parent ) && startsWithFiller( position.parent ) ) {
return true;
}
return false;
}
/**
* Removes the inline filler.
*
* @private
*/
_removeInlineFiller() {
const domFillerNode = this._inlineFiller;
// Something weird happened and the stored node doesn't contain the filler's text.
if ( !startsWithFiller( domFillerNode ) ) {
/**
* The inline filler node was lost. Most likely, something overwrote the filler text node
* in the DOM.
*
* @error view-renderer-filler-was-lost
*/
throw new CKEditorError( 'view-renderer-filler-was-lost: The inline filler node was lost.', this );
}
if ( isInlineFiller( domFillerNode ) ) {
domFillerNode.parentNode.removeChild( domFillerNode );
} else {
domFillerNode.data = domFillerNode.data.substr( INLINE_FILLER_LENGTH );
}
this._inlineFiller = null;
}
/**
* Checks if the inline {@link module:engine/view/filler filler} should be added.
*
* @private
* @returns {Boolean} `true` if the inline filler should be added.
*/
_needsInlineFillerAtSelection() {
if ( this.selection.rangeCount != 1 || !this.selection.isCollapsed ) {
return false;
}
const selectionPosition = this.selection.getFirstPosition();
const selectionParent = selectionPosition.parent;
const selectionOffset = selectionPosition.offset;
// If there is no DOM root we do not care about fillers.
if ( !this.domConverter.mapViewToDom( selectionParent.root ) ) {
return false;
}
if ( !( selectionParent.is( 'element' ) ) ) {
return false;
}
// Prevent adding inline filler inside elements with contenteditable=false.
// https://github.com/ckeditor/ckeditor5-engine/issues/1170
if ( !isEditable( selectionParent ) ) {
return false;
}
// We have block filler, we do not need inline one.
if ( selectionOffset === selectionParent.getFillerOffset() ) {
return false;
}
const nodeBefore = selectionPosition.nodeBefore;
const nodeAfter = selectionPosition.nodeAfter;
if ( nodeBefore instanceof ViewText || nodeAfter instanceof ViewText ) {
return false;
}
return true;
}
/**
* Checks if text needs to be updated and possibly updates it.
*
* @private
* @param {module:engine/view/text~Text} viewText View text to update.
* @param {Object} options
* @param {module:engine/view/position~Position} options.inlineFillerPosition The position where the inline
* filler should be rendered.
*/
_updateText( viewText, options ) {
const domText = this.domConverter.findCorrespondingDomText( viewText );
const newDomText = this.domConverter.viewToDom( viewText, domText.ownerDocument );
const actualText = domText.data;
let expectedText = newDomText.data;
const filler = options.inlineFillerPosition;
if ( filler && filler.parent == viewText.parent && filler.offset == viewText.index ) {
expectedText = INLINE_FILLER + expectedText;
}
if ( actualText != expectedText ) {
const actions = fastDiff( actualText, expectedText );
for ( const action of actions ) {
if ( action.type === 'insert' ) {
domText.insertData( action.index, action.values.join( '' ) );
} else { // 'delete'
domText.deleteData( action.index, action.howMany );
}
}
}
}
/**
* Checks if attribute list needs to be updated and possibly updates it.
*
* @private
* @param {module:engine/view/element~Element} viewElement The view element to update.
*/
_updateAttrs( viewElement ) {
const domElement = this.domConverter.mapViewToDom( viewElement );
if ( !domElement ) {
// If there is no `domElement` it means that 'viewElement' is outdated as its mapping was updated
// in 'this._updateChildrenMappings()'. There is no need to process it as new view element which
// replaced old 'viewElement' mapping was also added to 'this.markedAttributes'
// in 'this._updateChildrenMappings()' so it will be processed separately.
return;
}
const domAttrKeys = Array.from( domElement.attributes ).map( attr => attr.name );
const viewAttrKeys = viewElement.getAttributeKeys();
// Add or overwrite attributes.
for ( const key of viewAttrKeys ) {
domElement.setAttribute( key, viewElement.getAttribute( key ) );
}
// Remove from DOM attributes which do not exists in the view.
for ( const key of domAttrKeys ) {
if ( !viewElement.hasAttribute( key ) ) {
domElement.removeAttribute( key );
}
}
}
/**
* Checks if elements child list needs to be updated and possibly updates it.
*
* @private
* @param {module:engine/view/element~Element} viewElement View element to update.
* @param {Object} options
* @param {module:engine/view/position~Position} options.inlineFillerPosition The position where the inline
* filler should be rendered.
*/
_updateChildren( viewElement, options ) {
const domElement = this.domConverter.mapViewToDom( viewElement );
if ( !domElement ) {
// If there is no `domElement` it means that it was already removed from DOM.
// There is no need to process it. It will be processed when re-inserted.
return;
}
const inlineFillerPosition = options.inlineFillerPosition;
const actualDomChildren = this.domConverter.mapViewToDom( viewElement ).childNodes;
const expectedDomChildren = Array.from(
this.domConverter.viewChildrenToDom( viewElement, domElement.ownerDocument, { bind: true, inlineFillerPosition } )
);
// Inline filler element has to be created as it is present in the DOM, but not in the view. It is required
// during diffing so text nodes could be compared correctly and also during rendering to maintain
// proper order and indexes while updating the DOM.
if ( inlineFillerPosition && inlineFillerPosition.parent === viewElement ) {
addInlineFiller( domElement.ownerDocument, expectedDomChildren, inlineFillerPosition.offset );
}
const diff = this._diffNodeLists( actualDomChildren, expectedDomChildren );
let i = 0;
const nodesToUnbind = new Set();
// Handle deletions first.
// This is to prevent a situation where an element that already exists in `actualDomChildren` is inserted at a different
// index in `actualDomChildren`. Since `actualDomChildren` is a `NodeList`, this works like move, not like an insert,
// and it disrupts the whole algorithm. See https://github.com/ckeditor/ckeditor5/issues/6367.
//
// It doesn't matter in what order we remove or add nodes, as long as we remove and add correct nodes at correct indexes.
for ( const action of diff ) {
if ( action === 'delete' ) {
nodesToUnbind.add( actualDomChildren[ i ] );
remove( actualDomChildren[ i ] );
} else if ( action === 'equal' ) {
i++;
}
}
i = 0;
for ( const action of diff ) {
if ( action === 'insert' ) {
insertAt( domElement, i, expectedDomChildren[ i ] );
i++;
} else if ( action === 'equal' ) {
// Force updating text nodes inside elements which did not change and do not need to be re-rendered (#1125).
// Do it here (not in the loop above) because only after insertions the `i` index is correct.
this._markDescendantTextToSync( this.domConverter.domToView( expectedDomChildren[ i ] ) );
i++;
}
}
// Unbind removed nodes. When node does not have a parent it means that it was removed from DOM tree during
// comparision with the expected DOM. We don't need to check child nodes, because if child node was reinserted,
// it was moved to DOM tree out of the removed node.
for ( const node of nodesToUnbind ) {
if ( !node.parentNode ) {
this.domConverter.unbindDomElement( node );
}
}
}
/**
* Shorthand for diffing two arrays or node lists of DOM nodes.
*
* @private
* @param {Array.<Node>|NodeList} actualDomChildren Actual DOM children
* @param {Array.<Node>|NodeList} expectedDomChildren Expected DOM children.
* @returns {Array.<String>} The list of actions based on the {@link module:utils/diff~diff} function.
*/
_diffNodeLists( actualDomChildren, expectedDomChildren ) {
actualDomChildren = filterOutFakeSelectionContainer( actualDomChildren, this._fakeSelectionContainer );
return diff( actualDomChildren, expectedDomChildren, sameNodes.bind( null, this.domConverter ) );
}
/**
* Finds DOM nodes that were replaced with the similar nodes (same tag name) in the view. All nodes are compared
* within one `insert`/`delete` action group, for example:
*
* Actual DOM: <p><b>Foo</b>Bar<i>Baz</i><b>Bax</b></p>
* Expected DOM: <p>Bar<b>123</b><i>Baz</i><b>456</b></p>
* Input actions: [ insert, insert, delete, delete, equal, insert, delete ]
* Output actions: [ insert, replace, delete, equal, replace ]
*
* @private
* @param {Array.<String>} actions Actions array which is a result of the {@link module:utils/diff~diff} function.
* @param {Array.<Node>|NodeList} actualDom Actual DOM children
* @param {Array.<Node>} expectedDom Expected DOM children.
* @returns {Array.<String>} Actions array modified with the `replace` actions.
*/
_findReplaceActions( actions, actualDom, expectedDom ) {
// If there is no both 'insert' and 'delete' actions, no need to check for replaced elements.
if ( actions.indexOf( 'insert' ) === -1 || actions.indexOf( 'delete' ) === -1 ) {
return actions;
}
let newActions = [];
let actualSlice = [];
let expectedSlice = [];
const counter = { equal: 0, insert: 0, delete: 0 };
for ( const action of actions ) {
if ( action === 'insert' ) {
expectedSlice.push( expectedDom[ counter.equal + counter.insert ] );
} else if ( action === 'delete' ) {
actualSlice.push( actualDom[ counter.equal + counter.delete ] );
} else { // equal
newActions = newActions.concat( diff( actualSlice, expectedSlice, areSimilar ).map( x => x === 'equal' ? 'replace' : x ) );
newActions.push( 'equal' );
// Reset stored elements on 'equal'.
actualSlice = [];
expectedSlice = [];
}
counter[ action ]++;
}
return newActions.concat( diff( actualSlice, expectedSlice, areSimilar ).map( x => x === 'equal' ? 'replace' : x ) );
}
/**
* Marks text nodes to be synchronized.
*
* If a text node is passed, it will be marked. If an element is passed, all descendant text nodes inside it will be marked.
*
* @private
* @param {module:engine/view/node~Node} viewNode View node to sync.
*/
_markDescendantTextToSync( viewNode ) {
if ( !viewNode ) {
return;
}
if ( viewNode.is( 'text' ) ) {
this.markedTexts.add( viewNode );
} else if ( viewNode.is( 'element' ) ) {
for ( const child of viewNode.getChildren() ) {
this._markDescendantTextToSync( child );
}
}
}
/**
* Checks if the selection needs to be updated and possibly updates it.
*
* @private
*/
_updateSelection() {
// If there is no selection - remove DOM and fake selections.
if ( this.selection.rangeCount === 0 ) {
this._removeDomSelection();
this._removeFakeSelection();
return;
}
const domRoot = this.domConverter.mapViewToDom( this.selection.editableElement );
// Do nothing if there is no focus, or there is no DOM element corresponding to selection's editable element.
if ( !this.isFocused || !domRoot ) {
return;
}
// Render selection.
if ( this.selection.isFake ) {
this._updateFakeSelection( domRoot );
} else {
this._removeFakeSelection();
this._updateDomSelection( domRoot );
}
}
/**
* Updates the fake selection.
*
* @private
* @param {HTMLElement} domRoot A valid DOM root where the fake selection container should be added.
*/
_updateFakeSelection( domRoot ) {
const domDocument = domRoot.ownerDocument;
if ( !this._fakeSelectionContainer ) {
this._fakeSelectionContainer = createFakeSelectionContainer( domDocument );
}
const container = this._fakeSelectionContainer;
// Bind fake selection container with the current selection *position*.
this.domConverter.bindFakeSelection( container, this.selection );
if ( !this._fakeSelectionNeedsUpdate( domRoot ) ) {
return;
}
if ( !container.parentElement || container.parentElement != domRoot ) {
domRoot.appendChild( container );
}
container.textContent = this.selection.fakeSelectionLabel || '\u00A0';
const domSelection = domDocument.getSelection();
const domRange = domDocument.createRange();
domSelection.removeAllRanges();
domRange.selectNodeContents( container );
domSelection.addRange( domRange );
}
/**
* Updates the DOM selection.
*
* @private
* @param {HTMLElement} domRoot A valid DOM root where the DOM selection should be rendered.
*/
_updateDomSelection( domRoot ) {
const domSelection = domRoot.ownerDocument.defaultView.getSelection();
// Let's check whether DOM selection needs updating at all.
if ( !this._domSelectionNeedsUpdate( domSelection ) ) {
return;
}
// Multi-range selection is not available in most browsers, and, at least in Chrome, trying to
// set such selection, that is not continuous, throws an error. Because of that, we will just use anchor
// and focus of view selection.
// Since we are not supporting multi-range selection, we also do not need to check if proper editable is
// selected. If there is any editable selected, it is okay (editable is taken from selection anchor).
const anchor = this.domConverter.viewPositionToDom( this.selection.anchor );
const focus = this.domConverter.viewPositionToDom( this.selection.focus );
// Focus the new editing host.
// Otherwise, FF may throw an error (https://github.com/ckeditor/ckeditor5/issues/721).
domRoot.focus();
domSelection.collapse( anchor.parent, anchor.offset );
domSelection.extend( focus.parent, focus.offset );
// Firefox–specific hack (https://github.com/ckeditor/ckeditor5-engine/issues/1439).
if ( env.isGecko ) {
fixGeckoSelectionAfterBr( focus, domSelection );
}
}
/**
* Checks whether a given DOM selection needs to be updated.
*
* @private
* @param {Selection} domSelection The DOM selection to check.
* @returns {Boolean}
*/
_domSelectionNeedsUpdate( domSelection ) {
if ( !this.domConverter.isDomSelectionCorrect( domSelection ) ) {
// Current DOM selection is in incorrect position. We need to update it.
return true;
}
const oldViewSelection = domSelection && this.domConverter.domSelectionToView( domSelection );
if ( oldViewSelection && this.selection.isEqual( oldViewSelection ) ) {
return false;
}
// If selection is not collapsed, it does not need to be updated if it is similar.
if ( !this.selection.isCollapsed && this.selection.isSimilar( oldViewSelection ) ) {
// Selection did not changed and is correct, do not update.
return false;
}
// Selections are not similar.
return true;
}
/**
* Checks whether the fake selection needs to be updated.
*
* @private
* @param {HTMLElement} domRoot A valid DOM root where a new fake selection container should be added.
* @returns {Boolean}
*/
_fakeSelectionNeedsUpdate( domRoot ) {
const container = this._fakeSelectionContainer;
const domSelection = domRoot.ownerDocument.getSelection();
// Fake selection needs to be updated if there's no fake selection container, or the container currently sits
// in a different root.
if ( !container || container.parentElement !== domRoot ) {
return true;
}
// Make sure that the selection actually is within the fake selection.
if ( domSelection.anchorNode !== container && !container.contains( domSelection.anchorNode ) ) {
return true;
}
return container.textContent !== this.selection.fakeSelectionLabel;
}
/**
* Removes the DOM selection.
*
* @private
*/
_removeDomSelection() {
for ( const doc of this.domDocuments ) {
const domSelection = doc.getSelection();
if ( domSelection.rangeCount ) {
const activeDomElement = doc.activeElement;
const viewElement = this.domConverter.mapDomToView( activeDomElement );
if ( activeDomElement && viewElement ) {
doc.getSelection().removeAllRanges();
}
}
}
}
/**
* Removes the fake selection.
*
* @private
*/
_removeFakeSelection() {
const container = this._fakeSelectionContainer;
if ( container ) {
container.remove();
}
}
/**
* Checks if focus needs to be updated and possibly updates it.
*
* @private
*/
_updateFocus() {
if ( this.isFocused ) {
const editable = this.selection.editableElement;
if ( editable ) {
this.domConverter.focus( editable );
}
}
}
}
mix( Renderer, ObservableMixin );
// Checks if provided element is editable.
//
// @private
// @param {module:engine/view/element~Element} element
// @returns {Boolean}
function isEditable( element ) {
if ( element.getAttribute( 'contenteditable' ) == 'false' ) {
return false;
}
const parent = element.findAncestor( element => element.hasAttribute( 'contenteditable' ) );
return !parent || parent.getAttribute( 'contenteditable' ) == 'true';
}
// Adds inline filler at a given position.
//
// The position can be given as an array of DOM nodes and an offset in that array,
// or a DOM parent element and an offset in that element.
//
// @private
// @param {Document} domDocument
// @param {Element|Array.<Node>} domParentOrArray
// @param {Number} offset
// @returns {Text} The DOM text node that contains an inline filler.
function addInlineFiller( domDocument, domParentOrArray, offset ) {
const childNodes = domParentOrArray instanceof Array ? domParentOrArray : domParentOrArray.childNodes;
const nodeAfterFiller = childNodes[ offset ];
if ( isText( nodeAfterFiller ) ) {
nodeAfterFiller.data = INLINE_FILLER + nodeAfterFiller.data;
return nodeAfterFiller;
} else {
const fillerNode = domDocument.createTextNode( INLINE_FILLER );
if ( Array.isArray( domParentOrArray ) ) {
childNodes.splice( offset, 0, fillerNode );
} else {
insertAt( domParentOrArray, offset, fillerNode );
}
return fillerNode;
}
}
// Whether two DOM nodes should be considered as similar.
// Nodes are considered similar if they have the same tag name.
//
// @private
// @param {Node} node1
// @param {Node} node2
// @returns {Boolean}
function areSimilar( node1, node2 ) {
return isNode( node1 ) && isNode( node2 ) &&
!isText( node1 ) && !isText( node2 ) &&
node1.tagName.toLowerCase() === node2.tagName.toLowerCase();
}
// Whether two dom nodes should be considered as the same.
// Two nodes which are considered the same are:
//
// * Text nodes with the same text.
// * Element nodes represented by the same object.
// * Two block filler elements.
//
// @private
// @param {String} blockFillerMode Block filler mode, see {@link module:engine/view/domconverter~DomConverter#blockFillerMode}.
// @param {Node} node1
// @param {Node} node2
// @returns {Boolean}
function sameNodes( domConverter, actualDomChild, expectedDomChild ) {
// Elements.
if ( actualDomChild === expectedDomChild ) {
return true;
}
// Texts.
else if ( isText( actualDomChild ) && isText( expectedDomChild ) ) {
return actualDomChild.data === expectedDomChild.data;
}
// Block fillers.
else if ( domConverter.isBlockFiller( actualDomChild ) &&
domConverter.isBlockFiller( expectedDomChild ) ) {
return true;
}
// Not matching types.
return false;
}
// The following is a Firefox–specific hack (https://github.com/ckeditor/ckeditor5-engine/issues/1439).
// When the native DOM selection is at the end of the block and preceded by <br /> e.g.
//
// <p>foo<br/>[]</p>
//
// which happens a lot when using the soft line break, the browser fails to (visually) move the
// caret to the new line. A quick fix is as simple as force–refreshing the selection with the same range.
function fixGeckoSelectionAfterBr( focus, domSelection ) {
const parent = focus.parent;
// This fix works only when the focus point is at the very end of an element.
// There is no point in running it in cases unrelated to the browser bug.
if ( parent.nodeType != Node.ELEMENT_NODE || focus.offset != parent.childNodes.length - 1 ) {
return;
}
const childAtOffset = parent.childNodes[ focus.offset ];
// To stay on the safe side, the fix being as specific as possible, it targets only the
// selection which is at the very end of the element and preceded by <br />.
if ( childAtOffset && childAtOffset.tagName == 'BR' ) {
domSelection.addRange( domSelection.getRangeAt( 0 ) );
}
}
function filterOutFakeSelectionContainer( domChildList, fakeSelectionContainer ) {
const childList = Array.from( domChildList );
if ( childList.length == 0 || !fakeSelectionContainer ) {
return childList;
}
const last = childList[ childList.length - 1 ];
if ( last == fakeSelectionContainer ) {
childList.pop();
}
return childList;
}
// Creates a fake selection container for a given document.
//
// @private
// @param {Document} domDocument
// @returns {HTMLElement}
function createFakeSelectionContainer( domDocument ) {
const container = domDocument.createElement( 'div' );
Object.assign( container.style, {
position: 'fixed',
top: 0,
left: '-9999px',
// See https://github.com/ckeditor/ckeditor5/issues/752.
width: '42px'
} );
// Fill it with a text node so we can update it later.
container.textContent = '\u00A0';
return container;
}